salut,
exo2:
1) A= 3(x+8) +(x+2) (x-2)
A= 3×x+3×8+x²-2²
A= 3x+24+x²-4
A= x²+3x+20
3) C=3(x+5) +(x+5) (x-2)
C= (x+5) [ 3+(x-2) ]
C= (x+5) [ 3+x-2]
C= (x+5) [ x+1]
4) D=25x²-64
D= (5x)²-8²
D= (5x+8) (5x-8)
voilà☺
